From patchwork Tue Jul 11 20:33:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jens Axboe X-Patchwork-Id: 13309360 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 28FF9C0015E for ; Tue, 11 Jul 2023 20:33:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229637AbjGKUdk (ORCPT ); Tue, 11 Jul 2023 16:33:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44882 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230397AbjGKUdj (ORCPT ); Tue, 11 Jul 2023 16:33:39 -0400 Received: from mail-pg1-x535.google.com (mail-pg1-x535.google.com [IPv6:2607:f8b0:4864:20::535]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 56125B7 for ; Tue, 11 Jul 2023 13:33:38 -0700 (PDT) Received: by mail-pg1-x535.google.com with SMTP id 41be03b00d2f7-55b5a37acb6so540036a12.0 for ; Tue, 11 Jul 2023 13:33:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20221208.gappssmtp.com; s=20221208; t=1689107617; x=1689712417; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=ixQUY57vnvYb5HvRH5ijyFihp5oJ/szTZ8856/uqLoU=; b=sI/EhwbO/KOMFb7uDzGESwMGWUkuorv7KqjZikEwkCW+0t36HgzSjPtaR7itUyd0M2 SHnZ2gCDDMoHxCeO9HB1Z3MzwkTyeF3jBmz2F4QHoGwfa0yvgQrZa79pbXDxtYyVob1K HRAR0y/cbmJb62fG8vH5iKRyUuXhtWrVOD6nTA9i8SFhSBZnGn4GYmBRSbx2gsBy5CJk fNIK5hQGgLik6/2F4YzjVa829WpmPNBrQhYDN6PFnVLR2ArPoS7Eyn6d7Q3inkHCFF2U /AVXYeUiEnGnKC1NY6/qsKYspwRS4kDipl++OGWF0KYDplasu3M6dlE0DwIAOzX8z2j/ hkSw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689107617; x=1689712417; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=ixQUY57vnvYb5HvRH5ijyFihp5oJ/szTZ8856/uqLoU=; b=dAHeGrrTt5AP4YjBlu8alSUuTX8U0c2M7XPyjDib/tVzqaExv1JUsBdHf4l1DVoO5S NPj0CvOHwMxiOLDXeTPemQ7GU/yhNhH5uzXAB/6L2cPp6/xrAoJWRzyUGNnlnT6BacT6 V3QSTqNJDo2JfFnmTz57cKg4IENLlEju34h5XtbGfnXNcm+r5Hqazo0g+QJ92O0wxAlp HLx+NxGffJNDLJkwnO0f/CpGSMlYLOLCGPrP6r8FxPnV5qMCNpCYvn2FIU8NVmWl9aM9 sAcO3Ue4bhc30xHZdViMkj4XIZTXVR0db6N4dJBy+suFQNMwfeDGGegFBRJ6Gs9ctefU qBow== X-Gm-Message-State: ABy/qLaehiDjbxbaAs7xVHvoQK3LMFUzHqwiT/uA4GiwCBck2N5VEvcm td7cjKo3RmZl2Y5pwtvqs2A0IocZy3wl4ViixRw= X-Google-Smtp-Source: APBJJlE0Fdjl9niH1fLBogzYDLzZpwQEuTCuENjw7d/RyTpMB94Vv2knTegxp7PH5nQo9z3SCc2jMg== X-Received: by 2002:a05:6a20:4289:b0:12c:76d1:bcde with SMTP id o9-20020a056a20428900b0012c76d1bcdemr23311409pzj.4.1689107617361; Tue, 11 Jul 2023 13:33:37 -0700 (PDT) Received: from localhost.localdomain ([198.8.77.157]) by smtp.gmail.com with ESMTPSA id fk13-20020a056a003a8d00b0067903510abbsm2108081pfb.163.2023.07.11.13.33.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 11 Jul 2023 13:33:36 -0700 (PDT) From: Jens Axboe To: io-uring@vger.kernel.org, linux-xfs@vger.kernel.org Cc: hch@lst.de, andres@anarazel.de, Jens Axboe Subject: [PATCH 5/5] iomap: support IOCB_DIO_DEFER Date: Tue, 11 Jul 2023 14:33:25 -0600 Message-Id: <20230711203325.208957-6-axboe@kernel.dk> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230711203325.208957-1-axboe@kernel.dk> References: <20230711203325.208957-1-axboe@kernel.dk> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org If IOCB_DIO_DEFER is set, utilize that to set kiocb->dio_complete handler and data for that callback. Rather than punt the completion to a workqueue, we pass back the handler and data to the issuer and will get a callback from a safe task context. Using the following fio job to randomly dio write 4k blocks at queue depths of 1..16: fio --name=dio-write --filename=/data1/file --time_based=1 \ --runtime=10 --bs=4096 --rw=randwrite --norandommap --buffered=0 \ --cpus_allowed=4 --ioengine=io_uring --iodepth=16 shows the following results before and after this patch: Stock Patched Diff ======================================= QD1 155K 162K + 4.5% QD2 290K 313K + 7.9% QD4 533K 597K +12.0% QD8 604K 827K +36.9% QD16 615K 845K +37.4% which shows nice wins all around. If we factored in per-IOP efficiency, the wins look even nicer. This becomes apparent as queue depth rises, as the offloaded workqueue completions runs out of steam. Signed-off-by: Jens Axboe --- fs/iomap/direct-io.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c index 94ef78b25b76..bd7b948a29a7 100644 --- a/fs/iomap/direct-io.c +++ b/fs/iomap/direct-io.c @@ -130,6 +130,11 @@ ssize_t iomap_dio_complete(struct iomap_dio *dio) } EXPORT_SYMBOL_GPL(iomap_dio_complete); +static ssize_t iomap_dio_deferred_complete(void *data) +{ + return iomap_dio_complete(data); +} + static void iomap_dio_complete_work(struct work_struct *work) { struct iomap_dio *dio = container_of(work, struct iomap_dio, aio.work); @@ -167,6 +172,25 @@ void iomap_dio_bio_end_io(struct bio *bio) !(dio->flags & IOMAP_DIO_WRITE)) { WRITE_ONCE(iocb->private, NULL); iomap_dio_complete_work(&dio->aio.work); + } else if ((iocb->ki_flags & IOCB_DIO_DEFER) && + !(dio->flags & IOMAP_DIO_NEED_SYNC)) { + /* only polled IO cares about private cleared */ + iocb->private = dio; + iocb->dio_complete = iomap_dio_deferred_complete; + /* + * Invoke ->ki_complete() directly. We've assigned + * out dio_complete callback handler, and since the + * issuer set IOCB_DIO_DEFER, we know their + * ki_complete handler will notice ->dio_complete + * being set and will defer calling that handler + * until it can be done from a safe task context. + * + * Note that the 'res' being passed in here is + * not important for this case. The actual completion + * value of the request will be gotten from dio_complete + * when that is run by the issuer. + */ + iocb->ki_complete(iocb, 0); } else { struct inode *inode = file_inode(iocb->ki_filp);